Air tool



April R. VON SCHEVEN 2,197,626

AIR TOOL Filed Aug. 13, 1938 2 Sheets-Sheet 1 IN VENT OR.

ATTORNEY.

April 16, 1940.

R. VON SCHEVEN 2,197,626

AIR TOOL Filed Aug. 13, 1938 2 Sheets-Sheet 2 100 94 31 91 93 92 INVENTOR.

ATTORNEY.

Patented Apr. 1%, 1949 AIR TOOL

PATENT OFFICE Richard vcn Scheven, Ridgewood, N.-Y., assignor of one-third to Harry Nerd, Ridgewood, N. Y., and onethird to William ll. Nowak, Port Washington, N. Y.

Application Augustl 1938, Serial No. 224,741

'7 Claims.

This invention relates to air tools and more especially to such tools in which a single air cylind mounts a doubie-action piston.

isle objects of the invention, among others first to provide a light easily manipulated air tool, second, to provide an air tool which e manufactured at low cost, third, to proimprov'ul means for supporting the working part on the piston of a doublaaction singlemotor, fourth, to provide guide ed on the body of the air motor, L1, to 1 a mounting device for the tool WLAiCh permits quicl attaching and detaching the port or adapted to engage the material to be worked, sixth, to provide mounting means which include a pin mounted in the piston the air motor, and means mounted on the of the air motor for guiding a tool in a path, which may include a wheel and a ck, seventl'i, to provide an oil chamber so dissed that it may readily be filled with oil and an aperture leading into "the air motor the motor is at all times subject to atlon, eighth, the provision of an arrangenproved air ducts in the air motor to the power and action of the air motor, Hill, to provide air tool that gives a hamg action on a punch, chisel, or similar tool. objects will appear as the description eds.

rence is made to the drawings, in which: we 1 is a lengthwise section of one form, ure 2 i" a bottom View,

E'lgllll) is a section on the line 3-4; of Figure 1, r

ure 1 is a section on the line 4-4 of Figure 1, gure 5 is a. lengthwise section showing a ,ndrical working piece of carborundum,

Figure 6 is a top view of a saw and attaching bracket,

ure "1 is a side view of Figure 6, ure 8 a side view of an oblong abrasive and holder,

Fi ure 9 a bottom view of Figure 8,

ure lll is side View of a rasp,

Figure 11 is a lengthwise section thru a modifi cation,

Figure 12 is a section on the line i2'--i2 of Figure 11,,

Figure 18 is a section on the line l3--i3' of Figure 11,

Figure 1% is a side view of a third modification,

Figure 15 is a section on the line i5--|5- of Figure 14,

Figure 16 is a left end view of the form shown in Figure 14. o g

A single cylinder double action air motor of the same design is used throughout the three modifications shown in the drawings. The changes in the different modifications are external to the operating air motor. Referring now to Figs. 1, 2, 3, and l, inclusive, the air motor includes a cast iron housing it which includes a transverse bore 22 in the form of a. cylinder with the diameter of the bore larger on theright side. In order to provide a. strong durable device, a steel sleeve 23- conforming with the wall of the bore 22 is securely fixed therein. The left end 2% of the sleeve having the smaller diameter is cylindrical in form and mounts for horizontal to and fro sliding motion'theiein a piston 25 which has an enlarged right end 25 slidably mounted in the larger end or the sleeve On top of the housing 2! is a neck 21 which is internally threaded to receive the external threading of a can 28 which is hollow to provide an axial air chamber 2%; A nut M is threaded on the top of the cap 23 and secures the left end of a handle 32, which has a central air duct 33 which leads into the air chamber 29. At the right end of the handle 32 is a connector 34 which is adapted to joinan air hose of usual design. In the handle there is provided an annular oil pocket 35 which is accessible on the outside by removing the threaded set screw 36 for filling the chamber with oil. A duct 3'! leads into the air conduit 33 providing lubrication for the air motor. On the right circular end of the housing 2! threading it is provided for removably mounting an internally threaded cap 39 which has an axial circular projection 4E. The central outer face of projection cl has an internally threaded central bore 42.

Leading from the air chamber 29 is an air port :33 connected with'a central annular groove 34 formed on the-inner wall of the bore 22 and coinciding with holes 45 formed in the sleeve 23 so that as the air under pressure flows through these holes it enters an annular chamber 46 and presses against the right end 26 to push the piston'ili to the right. A T-shaped duct til provided in the piston 25 connects centrally at the right with a recess in the piston that is conical in outline. An annular groove 49 at the left end formed in the wall of the bore 22 and an annular groove 5| formed at the right end in the bore 22' by means of suitable air ports 52 in. the sleeve 23 connect the outlets 53 radially disposed in the housing 2| on the left and with outlets 5d at the right. By providing outlets at opposite ends of the stroke, I procure'a complete exhaustion of the air and therefore increase the speed and power of my air motor.

On the left end of the piston 25 by means of a vertical pin 56, an end piece extension Ellis securely mounted by means of a recess formed in the right wall' of said end piece which fits over the left end of the piston 25. A bolt 58 having a large bottom extends up through the end piece 57 and is secured thereon by means of a nut 59. A fiat arm SI extending to the right of a bracket 62 has two holes centrally formed at the right;

one for allowing the passage of the bolt 53 and. the other for receiving the lower end ofthe pin 56. A shoulder 63 formed on top of the enlarged end of the bolt 58 engages the under side of the arm (H to secure it against the bottom of the end piece 5?. Screws 5 3 secure the bracket 52 to a block 65. On the bottom isa layer of felt 66 and on the top are two oppositely-disposed spring clips 61 which may be lifted up by the finger to insert the ends of sandpaper, which is placed over the felt 66, when desired. An arm 68 is secured transversely on the bottom of the housing 2I by means of a screw 69, and a lengthwise slot H, the side walls of which engage the bolt 58. In operation the tool is held by the handle 32 and the felt 5t placed in contact with a surface to be polished, and the felt '85 moves at high speed back and forth through a range of in the air motor shown so that by moving the tool with the hand a, large area surface can be quickly polished. It will be noted that this modification is very light and convenient to handle.

Referring now to Fig. 5, a bracket '32 is substi tuted for the bracket 82 shown in Fig. 1, this bracket also having an aperture for receiving the upper part of the bolt 58 and a second aperture I4 for receiving the lower end of the pin 56. A right angled extension I5 from the bracket 72 has an axially bore stub 15 mounted on the outer face. A set screw I? is so mounted to lock in the bore a supporting pin I8 on the outer extension of which is a supporting casing 79 so formed as tosecurely hold a cylindrical abrasive 8 I. Referring now to Figures 6 and Z, a saw 82 may be substituted for the casing l9. Referring to Figures 8 and 9, a bracket 83 provided at the right with the apertures 73 and M- mounts at the left end a supporting casing 84 in which an oblong abrasive 85 is secured. Referring now to Figure 10, an arm 85 supports a rasp 8'! at the left and at the right is provided with apertures 13 and 14.

Referring now to Figures 11, 12 ,and.13, a cover 9| is substituted for the arm 32 of the modification shown in Figure 1 and at the right has an internally threaded opening for the attachment of an air hose, not shown. An air duct 93 leads to an air chamber 29 similar to that shown in Figure I. An oil chamber 9 8 is formed at the left and by a duct 95 conducts oil to the air chamber 29. A threaded cap I08 permits introduction of oil on the outside to the chamber 94. The sides of thecover 9| slightly below the top have lengthwise concave recesses 96 permitting the tool to be grasped by the thumb and fingers of a hand and permitting the palm of the hand to rest on the top of the housing to exert pressure thereon. The cover has also a downwardly-extending wall 91 enclosing all the parts of the air motor and the attaching device. An externally threaded cylindrical stub 98 is fittedin the bore 42 of the 75 projection II and supports a casting 99'thereon,

which is detachably fixed by means of an adjusting screw IIlI at the top. Opposed horizontal bores I02 in the lower side walls of the casting 99 provide bearings for the axles of two wheels I03 which may be ball bearing type of well known design. A bracket I04 has at the top inwardly projecting flanges I05 which provide locking walls for the wheels I03 at the top, or. tracks for the wheels in some positions of the tool. Ordinarily the wheels I03 run back and forth on the flat upper surface of the bracket IIM, when the piston is operated by thecompressed air. A flat metal plate It underlies a second flat metal plate I01 on each side of which is a depending apertured ear I I38. A block I 09 is held against movement by studs III, which have shoulders engaging under the plate I06 and locking nuts engaging on top of the plate If". A felt H3 is detachably mounted with the block I09 by means of spring pressed pins I I4 which engage apertures in the ears I08. The construction of the block I9 and the securing device shown in Figure 13, is no part of my invention and will be covered in a separate application by another inventor.

Referring to Figures 14, 15 and 16, a bracket Ht has on opposite sides parallel arms H! extending to the right and secured horizontally on the opposite sides of the housing M by means of screws II8. A steel bearing H9 mounting in a central cylindrical boss I20 has an hexagonal bore I2I at the left which connects with a smaller cylindrical bore I22 at the right and providing a shoulder which presents the hexagonal arm In of a chisel I 23 from the moving beyond a predetermined point at the right. The cylindrical end I25 of the arm I24 is chamfered and is so mounted that it receives hammering blows from the piston 25. In the form shown the stroke of the arm I24 is the stroke of the piston 25 is 3 so that the piston 25 accumulates stored energy through three quarters of this stroke therefore delivering a hard hammer blow on the end of the arm I24. To use the device for punching, or to substitute any other tool. is readily accomplished by mounting such a tool on a similar hexagonal arm I24. It will be understood that the rebound of the tool from the work automatically restores it to the hammer position of the end of the arm I24. This tool is very light in design and efficient in operation. Any suitable retaining device may be used to prevent the tool from leaving the bearing.

It will be noted that the design permits a maximum of interchangeability of parts with reference to an air motor and with reference to various supports, and now that I have disclosed my invention other changes will readily occur to those skilled in the art, parts may be substituted for parts, and parts may be omitted, all within the spirit and scope of the invention.

I claim:

1. A double-acting air tool, comprising in combination, a horizontally disposed chamber in the tool, a piston slidingly disposed in the chamber and extending at one side of the tool, an extension piece mounted on the end of the piston, a pin passing transversely through said extension piece and through said piston to securely lock said piece on the end of said piston, a vertical hole in said piece, a post in said piece having a round extension below said piece and a shoulder on said round extension for supporting a working device.

2. A double-acting air tool, comprising in combination, a horizontally disposed chamber, a piston slidingly disposed in said chamber and extending at one side of the tool, an extension piece mounted on the end of said piston, having a recess for fitting over the end of the piston, a pin passing through said piece and said piston to securely lock said piece on the end of said piston, a vertical hole in said piece, a bolt in said piece having a round extension below said piece, a-shoulder on said round extension for supporting a working portion under said piece, and a nut on the opposite end of said bolt for detachably mounting said bolt on said piece so that different working devices can be quickly attached.

3. A double-acting air tool comprising in combination, a horizontally disposed cylindrical chamber, a cylindrical piston slidingly disposed in said chamber and extending at one side of the tool, means mounted on the extended end of said piston for supporting a working portion thereon, a conduit leading from said cylindrical chamber toward the top of said tool, a hollowconnecting cap having a screw-threaded connection with the top of the tool and said conduit, a handle horizontally disposed, and having a hollow chamber and a transverse aperture by means of which the handle may be fitted over said cap, the hole in the cap connecting with said hollow handle chamber, and a nut for holding said handle on said cap, whereby different handles may be used with the tool.

4. A double-acting air tool, comprising in comcombination, a horizontally disposed chamber in the tool, a piston slidingly disposed in the chamber and extending at one side of the tool, an extension piece mounted on the end of the piston, a pin passing transversely through said extension piece and through said piston to securely lock said piece on the end of said piston, a vertical hole in said piece, a post in said piece having a round extension below said piece, a shoulder on said round extension for supporting a Working portion, and a bracket attached to the bottom of the tool and having a fiat slotted arm extending beneath the piston extension piece, a round extension of the post engaging said slot.

5. A double-acting air tool, comprising in combination, a horizontally disposed chamber in the tool, a piston slidingly disposed in the chamber and extending at one side of the tool, an extension piece mounted on the end of the piston, a pin passing transversely through said extension piece and through said piston to securely lock said piece on the end of said piston, a vertical hole in said piece, a post in said piece having a round extension below said piece, a shoulder on said round extension for supporting a working portion, and a pair of wheels mounted on the end of the tool opposite to the piston extension for engaging tracks on a working piece.

6. A double-acting air tool, comprising in combination, a horizontally disposed chamber in the tool, a piston slidingly disposed in the chamber and extending at one side of the tool, an extension piece mounted on the end of the piston, a pin passing transversely through said extension piece and through said piston to securely lock said piece, a shoulder on said round extension for supporting a working portion, and a pair of wheels mounted on the end of the tool opposite to the piston extension, said wheel mounting having a screw-threaded connection with said tool.

'7. A double-acting air tool, comprising in combination, a horizontally disposed chamber in the tool, a piston slidingly disposed in the chamber and extending at one side of the tool, an extension piece mounted on the end of the piston, a pin passing transversely through said extension piece and through said piston, to securely lock said piece on the end of said piston, a vertical hole in said piece, a post in said piece having a round extension below said piece, a shoulder on said round extension for supporting a working portion, and a bracket attached to the bottom of the tool and having a fiat slotted arm extending beneath the piston extension piece, the round extension of the post engaging said slot, said bracket having a screw-threaded connection with the bottom of said tool.

RICHARD VON SCHEVEN. 

